Weight and balance equipment



June 29, 1965 c, c, sMlTH WEIGHT AND BALANCE EQUIPMENT Filed Jan. 22, 1962 INVENTOR. CARROLL C. SMITH United States Patent assignments, to the UnitedStates of America as repre- V sented by the Secretary of the Navy Filed Jan. 22, 1962, Ser. No. 167,986 3 Claims. (Cl. 73-65) This invention relates to a weight and balancing device and more particularly to a weight and balancing device for use for military weapons such as torpedoes, selfpropelled mines, and the like to apply a righting moment thereto necessary to obtain a predetermined balanced condition thereof. It is the usual practice, in the manu facture of torpedoes, self-propelled mine vehicles and the like to arrange the various components of the weapon with the center of gravity thereof disposed beneath the center of buoyancy in such manner that the vehicle will assume a predetermined angular or zero-roll position about its axis as the vehicle is self-propelled through the water such that the vehicle may be regarded as right side up or riding on an even keel in order to obtain the best results therefrom. When the vehicle is driven by a single constant speed rotating propeller, the torque applied to the propeller by the propelling mechanism causes the vehicle to assume a position within the water such that the center of gravity thereof is no longer directly beneath the center of buoyancy but is displaced laterally therefrom by an angle from the vertical sufiicient to impart to the vehicle a torque in equality with and opposite to the torque applied to the propeller by the propelling mechanism. This transverse displacement of the center of gravity of the vehicle sufficient to counterbalance the reaction torque developed by the propulsion system is referred to herein as the righting moment of the vehicle. In practice this righting moment is usually expressed in pound-inches. The value ofthis. righting torque is known and it is the usual practice, therefore, to displace the center of gravity of the vehicle by shifting relatively heavy weights around the inner circumference of the casing of the vehicle until a predetermined righting moment has been applied thereto such that the vehicle will assume and maintain a predetermined ballasted position within the water of zero roll while the vehicle is self-propelled and thereafter clamping the weights in their set positions within the casing of the vehicle. In a torpedo, for example, it has been found necessary because of space limitations within the casing of the vehicle, to apply a righting moment to the nose section, the body section and the tail section respectively, the sum total of these three moments being exactly equal to the righting moment of the assembled torpedo required to maintain it in zero roll position when driven through the water under its own power.

In devices of this general character heretofore devised for applying a righting moment to a torpedo, for example, during the fabrication thereof, itis the usual practice to pivotally support the various sections of the torpedo body by a pivotal structure secured thereto at each end thereof for rotation of the body about a horizontal axis and to apply a righting moment thereto by a lever and weight arrangement in which the lever is moved about the axis of the body as the body is rotated about the axis to different settings. Such devices have not proved altogether satisfactory by reason of the fact that the pivotal structure employed therewith interferred with free access to the interior of the casing necessary for proper adjusting of the ballasted weights therein, and the moment applied thereto by the lever and weight arrangement varied with the angular position of the lever from an initial horizontal position as the casing was rotated to a new setting. This required continual adjustment of its axis to any desired position.

3,191,429 Patented June 29, 1965 the weight along the lever to maintain a constant righting moment.

The device of the present invention possesses all of the advantages of the prior art devices and none of the foregoing disadvantages. In accordance with the present invention the body to be ballasted for righting moment is suspended in an annular sling at one or both ends thereof, as will more clearly appear as the description proceeds, and in addition thereto a constant torque is applied to the body regardless of the degree of rotation thereof from the initial zero roll position.

One of the objects of the present invention is to provide a new and improved apparatus for use in ballasting individual sections of mine vehicles and torpedoes for righting moment. 7

Another of the objects is to provide new and improved apparatus for applying a constant righting torque thereto while the torpedo is in a position of rotation about its horizontal axis during a cycle of balancing operations. Still other objects, advantages and improvements will be apparent from the following description taken in connection with the accompanying drawing of which:

FIG. 1 is a view in elevation and somewhat in perspective of the test device of the instant invention according to a preferred embodiment thereof and the tail or afterbody section of a torpedo supported thereby:

FIG. 2 is a view similar to FIG. 1 on which is shown the nose section of a torpedo carried by the device in a test position;

FIG. 3 is an elevational view of the central body poltion of a torpedo carried by the device in a test position;

FIG. 4 is a view'of the nose section adaptor; and

FIG. 5 is a View of the afterbody adaptor.

Referring now to the drawing for a more complete understanding of the invention and more particularly to FIG. 1 thereof there is shown thereon a pair of dollies indicated generally by the numerals 10 and 10' each comprising a framework 11 supported by heavy casters 12. The framework 11 is generally of boxlike configuration and carries at the top portion thereof a steel V-belt sheave 13 mounted on a shaft 14 which is free to rotate in a pair of ball-bearing pillow blocks 15 secured to the framework substantially as shown. An endless wire rope sling or cable passes over the V-belt sheave 13 and supports the foreward end of the afterbody portion 16 of a torpedo in such manner that it may be easily rotated about afterbody portion is provided with an adaptor 17, FIG. 5, secured to the end of the propeller shaft and provided with an axially disposed projection for establishing a connection to a ball-bearing support 18 secured to the frame 11 of dolly 16, in such manner that the axis of the afterof weight 21 is just sufficient to apply a predetermined righting moment to the afterbody. A second weight or plumb bob 22, as shown more clearly on FIG. 2, is carried by line 23 secured at 24 to the uppermost end portion of the afterbody when the afterbody is in the zero roll position. A reference line or mark 25 applied to the lower end portion of the afterbody provides a line of reference which, together with the line 23, is employed for indicating when the afterbody is in the zero roll position assumed by the afterbody when the ballast weights have been positioned therein to balance the righting moment applied to the afterbody by the weight 21 through line 19.

On FIG. 2 is shown the nose portion or casing 26 of a torpedo carried by the dollies 10 and 10' for rotation The opposite end of theprovided with a nose adaptor 27 for establishing a pivotal connection to the dolly 16 in such manner that the axis of the nose is horizontal when supported in the test position as shown' The nose portion has a righting moment applied thereto by line 19 and weight 21, the weight in this case having just sufficient mass to apply the proper righting moment to the nose. The zero roll position of the nose section is made manifest by line 23 and its coincidence with mark 25, as illustrated. It will be understood that when weight 21' is first applied to the nose piece 26 the mark 25 will be moved clockwise as viewed in the drawing to a position which thetorpedo would assume in the water when being self-propelled if no additional righting moment had been applied thereto. When the ballast weights have been properly adjusted and clamped in their adjusted positions within the casing of the nose piece 26, the torque applied by the ballast' weights is just sufiicient to apply a righting moment to the nose piece to cause the nose piece to move about the axis thereof and come to rest in the zero roll position as shown on the drawing.

OnFIG. 3 is shown the main body portion 2-8 of the torpedo suspended by the pair of Wire rope slings 29 passing over the sheaves 13 of the dollies 1t) and in such manner that the main body portion 2s is freely rotatable about the horizontal axis thereof. The main body portion 23 is provided with a line 19 Wrapped thereabout to one end of which is secured a weight 21" of just suiiicient mass to apply a righting torque of predetermined value to the body 28, as in the case of the tail portion 16 of FIG. 1 and the nose portion 26 of FIG, 2. The main body portion 28 is adjusted to the zero roll position by shifting and locking the ballast weights therein in their proper settings, this position .of the main body portion 28 being made manifest by the plumb line comprising line 23 and plumb bob 22, in connection with a mark on the end of the main body portion 23.

After the nose section,'tail or afterbody section and main body section have been balanced they are reassembled as a unit, the nose and afterbody adaptors of FIGS. 4 and 5 respectively are removed and the balancing operations of the torpedo are now complete. applied to the assembledsections of the assembled torpedo by the ballast weights respectively disposed therein is just suificient to counter-balance the torque applied to the torpedo by the self-propelling mechanism such that the. torpedo will be in the zero roll position as it moves through'the water under its own power.

Whereas the nose adaptor, in the illustrated example, is fastened to the nose 26 of the torpedo by four screws 31, it will be understood that other well known instrumentalities and means for securing the adaptor to the- The momentfactory results, it is not so limited as it will be apparent to those skilled in the art, after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, in the appended claims to cover all such changes and modifications.

What is claimed as new and desired to be secured by Letters Patent of the United States is:-

1. A weight and'balancing'device comprising a pair of wheeled dollies, one of said dollies having a grooved puliey thereon for rotation about a horizontal axis, an endless wire rope sling over said pulley for supporting I an end portion of a self propelled cylindrical underwater object to be balanced in a zero roll' position for rotation about a horizontal axis concentric with the object, means on said cylindrical underwater object for indicating the zero roll position thereof, means on the other dolly for pivotally mounting the object atthe other end thereof for rotation about said axis, and means for applying a constant righting moment to said object comprising a weight suspended from the outer peripheral surface of the object and of just sufficient mass to bring the object into a predetermined state of balance while the object is self-propelled through the water.

2. A weight and balance device comprising a pair of wheeled dollies, eachof said dollies having a grooved pulley thereon pivoted'for rotation about a horizontal axis, a pair of endless wire rope slings, each of said slings being disposed over a respective oneof said pulleys for supporting a self propelled underwater cylindrical object to be balanced for rotation about a horizontal axis concentric therewith andparallel to the axis of rotation of the pulleys, means for applying a predetermined righting moment to said object while theobject is supported by said slings, said object being the main body portion of a marine torpedo, said means for applying said righting moment to said object comprising a mass suspended by a line wrapped about the'outer cylindrical surface of said main body portion, the Weight of the mass being just sufficient to rotate the object to a predetermined position of balance in zero roll position from an initial position of unbalance with respect to said predetermined position, and means on said object for indicating the zero roll position thereof.

3. A device according to claim 2 including a plumb line freely suspended from an upper'end portion of said cylindrical object and a mark on a lower end portion of the object cooperating therewith for indicating when the object is in said zero roll position.

References Cited by the Examiner UNITED sTATEs PATENTS 834,765 10/06 Sechler 33-216 1,327,838 1/20 Naylor 73-99 1,690,519 11/28 Adolfsson 214-1 X 1,876,290 9/32 Hanna 214-1 X 1,916,025 6/33 Skeehan 214-1 X 2,977,803 4/61 'Green 73-481 RICHARD c. QUEISSER, Primary Examiner.

ROBERT L. EVANS, Examiner. 

1. A WEIGHT AND BALANCING DEVICE COMPRISING A PAIR OF WHEELED DOLLIES, ONE OF SAID DOLLIES HAVING A GROOVED PULLEY THEREON FOR ROTATION ABOUT A HORIZONTAL AXIS, AN ENDLESS WIRE ROPE SLING OVER SAID PULLEY FOR SUPPORTING AN END PORTION OF A SELF PROPELLED CYLINDRICAL UNDERWATER OBJECT TO BE BALANCED IN A ZERO ROLL POSITION FOR ROTATION ABOUT A HORIZONTAL AXIS CONCENTRIC WITH THE OBJECT, MEANS ON SAID CYLINDRICAL UNDERWATER OBJECT FOR INDICATING THE ZERO ROLL POSITION THEREOF, MEANS ON THE OTHER DOLLY FOR PIVOTALLY MOUNTING THE OBJECT AT THE OTHER END THEREOF FOR ROTATION ABOUT SAID AXIS, AND MEANS FOR APPLYING A CONSTANT RIGHTING MOMENT TO SAID OBJECT COMPRISING A WEIGHT SUSPENDED FROM THE OTHER PERIPHERAL SURFACE OF THE OBJECT AND OF JUST SUFFICIENT MASS TO BRING THE OBJECT INTO A PREDETERMINED STATE TO BALANCE WHILE THE OBJECT IS SELF-PROPELLED THROUGH THE WATER. 